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-rw-r--r--MdePkg/Library/BaseMemoryLibMmx/X64/CopyMem.asm68
1 files changed, 68 insertions, 0 deletions
diff --git a/MdePkg/Library/BaseMemoryLibMmx/X64/CopyMem.asm b/MdePkg/Library/BaseMemoryLibMmx/X64/CopyMem.asm
new file mode 100644
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--- /dev/null
+++ b/MdePkg/Library/BaseMemoryLibMmx/X64/CopyMem.asm
@@ -0,0 +1,68 @@
+;------------------------------------------------------------------------------
+;
+; Copyright (c) 2006, Intel Corporation
+; All rights reserved. This program and the accompanying materials
+; are licensed and made available under the terms and conditions of the BSD License
+; which accompanies this distribution. The full text of the license may be found at
+; http://opensource.org/licenses/bsd-license.php
+;
+; THE PROGRAM IS DISTRIBUTED UNDER THE BSD LICENSE ON AN "AS IS" BASIS,
+; WITHOUT WARRANTIES OR REPRESENTATIONS OF ANY KIND, EITHER EXPRESS OR IMPLIED.
+;
+; Module Name:
+;
+; CopyMem.asm
+;
+; Abstract:
+;
+; CopyMem function
+;
+; Notes:
+;
+;------------------------------------------------------------------------------
+
+ .code
+
+InternalMemCopyMem PROC USES rsi rdi
+ mov rsi, rdx ; rsi <- Source
+ mov rdi, rcx ; rdi <- Destination
+ lea r9, [rdi + r8 - 1] ; r9 <- End of Destination
+ cmp rsi, rdi
+ mov rax, rdi ; rax <- Destination as return value
+ jae @F
+ cmp r9, rsi
+ jae @CopyBackward ; Copy backward if overlapped
+@@:
+ xor rcx, rcx
+ sub rcx, rsi
+ and rcx, 7 ; rcx + rsi aligns on 8-byte boundary
+ jz @F
+ cmp rcx, r8
+ cmova rcx, r8
+ sub r8, rcx ; r8 <- remaining bytes to copy
+ rep movsb
+@@:
+ mov rcx, r8
+ and r8, 7
+ shr rcx, 3 ; rcx <- # of Qwords to copy
+ jz @CopyBytes
+@@:
+ DB 48h, 0fh, 6fh, 06h ; movq mm0, [rsi]
+ DB 48h, 0fh, 0e7h, 07h ; movntq [rdi], mm0
+ add rsi, 8
+ add rdi, 8
+ loop @B
+ mfence
+ jmp @CopyBytes
+@CopyBackward:
+ mov rdi, r9 ; rdi <- End of Destination
+ lea rsi, [rsi + r8 - 1] ; rsi <- End of Source
+ std ; set direction flag
+@CopyBytes:
+ mov rcx, r8
+ rep movsb ; Copy bytes backward
+ cld
+ ret
+InternalMemCopyMem ENDP
+
+ END